Is using dual subs to create "full range towers" a good idea

[jcisbig]

Hey All,

I need to know if this is a dumb idea or a valid idea.

Let's say that you had two tower speakers that played down to 45hz. That's decent, but no where near full range. You'd have to put a sub into the mix to get any real low end out of that system. What if you had two subs that had a pair of RCA ins/outs integrated into the amp. Could you run RCA from a pre-out on a processor into the sub, use the sub's internal crossover to blend it with the tower, and then run the RCA out of the sub amp to an amplifier that would then feed your speaker? This way you'd have a sub next to each tower and would essentially create a "full range" tower speaker with dual subs, right?

Questions:
1) Would running the audio signal through the sub amp degrade the sound quality noticeably? (probably depends on the subwoofer and the amp?)
2) Would you set up the processor receiver as a 2.0, 5.0, or 7.0 system in this case?
3) If yes to #2, then does the LFE in movies get routed to both of the L/R "towers"?

Thanks!

[garbulky]

Nov 11, 2013 13:43:54 GMT -5 jcisbig said:

Hey All,

I need to know if this is a dumb idea or a valid idea.

Let's say that you had two tower speakers that played down to 45hz. That's decent, but no where near full range. You'd have to put a sub into the mix to get any real low end out of that system. What if you had two subs that had a pair of RCA ins/outs integrated into the amp. Could you run RCA from a pre-out on a processor into the sub, use the sub's internal crossover to blend it with the tower, and then run the RCA out of the sub amp to an amplifier that would then feed your speaker? This way you'd have a sub next to each tower and would essentially create a "full range" tower speaker with dual subs, right?

Questions:
1) Would running the audio signal through the sub amp degrade the sound quality noticeably? (probably depends on the subwoofer and the amp?)
2) Would you set up the processor receiver as a 2.0, 5.0, or 7.0 system in this case?
3) If yes to #2, then does the LFE in movies get routed to both of the L/R "towers"?

Thanks!

1) Depends on the quality of the passthrough. I personally wouldn't do that. I would instead split the signal before the sub.
3) Good question.
As for dual subs. This is a good idea. It also helps reduce room irregularities.

[jcisbig]

Thanks for the reply garbulky,

Would you split it with something like this:
www.monoprice.com/Product?c_id=102&cp_id=10218&cs_id=1021803&p_id=663&seq=1&format=2

Then just run one RCA to the sub and another to the amp?

This method shouldn't cause any reduction in sound quality, unless the splitter cable is doing something strange, right?

[jlafrenz]

The cable you linked to would be the type of cable to use, but I would opt for a better one. Monoprice should have some with better shielding. What is being discussed here is a couple of different things. Splitting the sub output and running to to dual subs is fine, but they will both play the same thing. If you are wanting to have each sub only play the lows for a particular channel, this is a bit different. You can run from the amp to the high level inputs on a sub amp and accomplish this. Will you be using the equipment in your signature or what subs do you have in mind?

I know I just threw a lot out there. With a little more information about what you have and exactly what you want to accomplish, we can get you the necessary information and parts list.

[garbulky]

Nov 11, 2013 13:54:37 GMT -5 jcisbig said:

Thanks for the reply garbulky,

Would you split it with something like this:
www.monoprice.com/Product?c_id=102&cp_id=10218&cs_id=1021803&p_id=663&seq=1&format=2

Then just run one RCA to the sub and another to the amp?

This method shouldn't cause any reduction in sound quality, unless the splitter cable is doing something strange, right?

That's kind of the basic idea for the cable (you'll need two I think one for the left and one for the right). However, I think I should bow out here. I have little experience with what you are trying to do. Hopefully jlafrenz and the other members can give you better information

[jcisbig]

jlafrenz,

No, I wouldn't be doing this with my current setup. My friend is looking at picking a couple of SVS PB12NSDs for his system that has the Emp Tek towers. I was just curious to find out if there was a good way (or if it was good at all) to use the subs to make the emp tek speakers full range. He'll be using a UMC-1 and UPA-500 in the system if that's helpful.

Overall, I'm just really curious if it makes any sense/is easily possible to "pair" a tower with a sub and treat it like it is one "speaker".

I'm also curious to know how a processor would handle the LFE in a movie without a sub hooked up to the sub channel. Hmm, maybe we need THREE subs!

[jlafrenz]

It doesn't look like the SVS subs your friend will be getting have the high level inputs on them to connect the way I described. In this situation he would just be running the UMC-1 in stereo mode with a "Y" splitter on the subs. He would need to set the crossover in the UMC-1 to the level of his liking that blends in with those towers. When you connect the subs in this fashion, all of the low end is going to be combined and played through both subs as opposed to a true left/right channel subwoofer.

[jcisbig]

Hmm. Why wouldn't it work to do it the way I outlined in my original post?

If a sub did have high level inputs, like my HSU does, how would you hook up the subs and towers?

[GreenKiwi]

If I thought that stereo subs were important (maybe if they were getting crossed over above 60Hz), you could take the approach of getting 3 RCA splitters and connecting it such that the main L&R are split, L to one sub R to the other. Then the third splitter is on the .1 sub output and it goes to both subs.

Do your friend already have the UMC-200? Otherwise he could look for a pre-pro with dual sub outs.

[jlafrenz]

Nov 11, 2013 19:21:19 GMT -5 jcisbig said:

Hmm. Why wouldn't it work to do it the way I outlined in my original post?

If a sub did have high level inputs, like my HSU does, how would you hook up the subs and towers?

You could connect it the way you originally described. I had to actually look at the manual for the SVS to see what RCA connections it had.

[unsound]

What I did was to set my Front speakers to full on the UMC-1 and Sub to none. Emotiva tells me this will get the .1 sent to the Fronts (not in Direct mode, though). I then use a MiniDSP to do the crossover and some room-correction. In this setup I only have 2 speakers and 1 sub.

I have the EMPs and the PB-12 NSD in a different set-up. But, I'm not running them in the way you're thinking. If the speakers can be placed reasonably away from boundaries, you could use the splitter to feed the EMPs a full-range signal and then use the sub's crossover to integrate it with the speakers. You will, of course, miss out on the lower-frequencies sent to the surrounds in this manner.
You could also use a splitter on the sub-out and feed that to the subs (you wouldn't set your sub to none in this case). The subs will then get the full-range signal of the fronts, the lower frequencies of the surrounds and also the .1. However, you may run into issues with setting the sub volume to be appropriate for 2 ch music and x.1 channel movies.

I hope that makes sense!

[jcisbig]

Ok, thanks for all the replies! I guess the best thing to do will be to try out a few different things and see which sounds best!

[Gary Cook]

In a similar situations this is what I used to do (different equipment back then of course, but I'll substitute Emotiva hardware in the example);

For music:
UMC-200 (LF) --(RCA)---> Splitter 1 --(RCA)---> Subwoofer (LF) (set cross over between 60hz and 90 hz with 24 db slope)
                                                                     --(RCA)---> XPA-5 (LF)-----> Full Range Speaker (LF)

UMC-200 (RF) --(RCA)---> Splitter 1 --(RCA)---> Subwoofer (RF) (set cross over between 60hz and 90 hz with 24 db slope)
                                                                     --(RCA)---> XPA-5 (RF)-----> Full Range Speaker (RF)

For movies;
UMC-200 (LFE) --(XLR)---> Splitter 2 --(XLR)---> Subwoofer (LF) (Set the UMC-200 cross over the same as the sub cross over above)
                                                                       --(XLR)---> Subwoofer (RF) (Set the UMC-200 cross over the same as the sub cross over above)


The above cross over suggestions are nothing more than a place to start, you will need to fine tune them to suite the equipment and the room acoustics.


Cheers
Gary